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81.
报道了沙棘木蠹蛾性信息素的结构及组分,并报道了不同组分:顺-3-十四碳烯醇;反-3-十四碳烯醇;顺-3-十四碳乙酸酯;反-3-十四碳乙酸酯;顺-7-十四碳烯醇;顺-7-十四碳乙酸酯;顺-9-十四碳乙酸酯的室内触角电位反应和林间诱捕试验。林间诱蛾结果表明2组分和5组分的诱蛾活性高于其它组合。  相似文献   
82.
Andrographolide (ANDRO) is a lactone diterpenoid compound present in the medicinal plant Andrographis paniculata which is clinically applied for multiple human diseases in Asia and Europe. The pharmacological activities of andrographolide have been widely demonstrated, including anti-inflammation, anti-cancer and hepatoprotection. However, the pharmacological mechanism of andrographolide remains unclear. Therefore, further characterization on the kinetics and molecular targets of andrographolide is essential. In this study, we described the synthesis and characterization of a novel fluorescent andrographolide derivative (ANDRO-NBD). ANDRO-NBD exhibited a comparable anti-cancer spectrum to andrographolide: ANDRO-NBD was cytotoxic to various types of cancer cells and suppressed the migration activity of melanoma cells; ANDRO-NBD treatment induced the cleavage of heat shock protein 90 (Hsp90) and the downregulation of its client oncoproteins, v-Src and Bcr-abl. Notably, ANDRO-NBD showed superior inhibitory effects to andrographolide in all anticancer assays we have performed. In addition, ANDRO-NBD was further used as a fluorescent probe to investigate the uptake kinetics, cellular distribution and molecular targets of andrographolide. Our data revealed that ANDRO-NBD entered cells rapidly and its fluorescent signal could be detected in nucleus, cytoplasm, mitochondria, and lysosome. Moreover, we demonstrated that ANDRO-NBD was covalently bound to several putative target proteins of andrographolide, including NF-κB and hnRNPK. In summary, we developed a fluorescent andrographolide probe with comparable bioactivity to andrographolide, which serves as a powerful tool to explore the pharmacological mechanism of andrographolide.  相似文献   
83.
Oncogenic transformation of normal cells often involves epigenetic alterations, including histone modification and DNA methylation. We conducted whole-genome bisulfite sequencing to determine the DNA methylomes of normal breast, fibroadenoma, invasive ductal carcinomas and MCF7. The emergence, disappearance, expansion and contraction of kilobase-sized hypomethylated regions (HMRs) and the hypomethylation of the megabase-sized partially methylated domains (PMDs) are the major forms of methylation changes observed in breast tumor samples. Hierarchical clustering of HMR revealed tumor-specific hypermethylated clusters and differential methylated enhancers specific to normal or breast cancer cell lines. Joint analysis of gene expression and DNA methylation data of normal breast and breast cancer cells identified differentially methylated and expressed genes associated with breast and/or ovarian cancers in cancer-specific HMR clusters. Furthermore, aberrant patterns of X-chromosome inactivation (XCI) was found in breast cancer cell lines as well as breast tumor samples in the TCGA BRCA (breast invasive carcinoma) dataset. They were characterized with differentially hypermethylated XIST promoter, reduced expression of XIST, and over-expression of hypomethylated X-linked genes. High expressions of these genes were significantly associated with lower survival rates in breast cancer patients. Comprehensive analysis of the normal and breast tumor methylomes suggests selective targeting of DNA methylation changes during breast cancer progression. The weak causal relationship between DNA methylation and gene expression observed in this study is evident of more complex role of DNA methylation in the regulation of gene expression in human epigenetics that deserves further investigation.  相似文献   
84.
Gao  Hua  Wang  Dan  Wang  Yu-Ling  Mao  Jie-Ping  Jiang  Sen  Yang  Xin-Ling 《Molecular biology reports》2021,48(4):3079-3087
Molecular Biology Reports - Neuroinflammation is the key factor associated with the progression of Parkinson’s disease (PD). Pramipexole (PPX) has anti-inflammatory and antioxidant...  相似文献   
85.
昆虫病原线虫(Entomopathogenic nematodes)是业已商业化的昆虫寄生性天敌,对农林和卫生等重要害虫具有安全和有效的控制作用.这类线虫与环境生物和非生物因素存在密切的联系.影响昆虫病原线虫的环境生物因素包括同类线虫、共生细菌、寄主昆虫、寄生真菌以及其它昆虫病原物等;影响昆虫病原线虫的环境非生物因素主要有土壤类型、温湿度、盐度、紫外线等.本文从昆虫病原线虫与环境生物、非生物因素的关系综述这类线虫的研究进展,为昆虫病原线虫的研发和应用提供参考.  相似文献   
86.
Leaves of common deciduous trees: Aesculus hippocastanum and Tilia spp. from three parks within the urban area of Belgrade (Serbia) were studied as biomonitors of trace elements (Cr, Fe, Ni, Cu, Zn, and Pb) atmospheric pollution. The seasonal trace elements accumulation (September/May) in the leaves, and their temporal trends, were assayed in a multy-year period (2002–2006). Significant seasonal accumulation was evident in samples of A. hippocastanum for: Cr, Fe, Ni, Zn, and Pb, as well as in Tilia spp. leaves, except for Zn. For Cu, no regular seasonal accumulation was observed in leaves of the studied species. Decreasing temporal trend in leaf tissue concentrations were evident for Pb in A. hippocastanum (16.0 μg g?1 in September of 2002 to 4.6 μg g?1 in September of 2006) which is in accordance with the bulk atmospheric deposition measurements. The leaf Cu concentrations were the highest at one of the studied sites, also marked previously with extremely high atmospheric Cu loadings by some other monitoring (bulk deposition, particulate matter, moss) surveys. Decreasing Cu concentrations temporal trend at that site in the leaves of A. hippocastanum was evident through the studied years and also confirmed with the bulk deposition measurements. The Cr, Fe, Ni, and Zn leaf tissue concentrations remained at about the same level in the studied species throughout the experiment and no agreement was observed with the bulk deposition data. Comparing the studied biomonitors, the leaves of A. hippocastanum showed significantly higher elements accumulation and more consistency than Tilia spp., so it may be considered as more suitable species for assessment of Pb and Cu atmospheric pollution.  相似文献   
87.
88.
昆虫气味结合蛋白的研究进展   总被引:1,自引:0,他引:1  
摘要: 昆虫主要依赖其复杂且灵敏的化学感受系统来识别并区分外界环境中的各种化学信号。嗅觉是负责嗅觉信号传导的感官方式,能够引起昆虫觅食、产卵、交配和躲避天敌等对生存和繁殖至关重要的行为反应。在嗅觉感知过程中,气味结合蛋白(odorant binding proteins, OBPs)最先与外界脂溶性化学物质相互作用,并将其转运至化学受体神经元上,激活树突膜表面分布的嗅觉受体(olfactory receptors, ORs),是嗅觉系统正常运行的必需蛋白。近年来,随着高通量测序和分子生物学技术的快速发展,越来越多的昆虫OBPs相继得以鉴定并开展功能研究。昆虫OBPs是一类可溶性的小分子蛋白,一般由6个α-螺旋构成一个稳定、紧密的疏水性结合腔,其构象变化因昆虫种类和配体结构不同而有所差异。OBPs的分布不受限于嗅觉器官,还在口器、足、中肠、腺体等非嗅觉组织中表达,具有嗅觉识别、味觉感受、营养物质转运、信息素合成与释放、组织发育与分化等生理功能。OBPs行使以上功能的共同特性为结合和溶解包括信息素组分、普通气味分子和非挥发性物质等的疏水性小分子物质。昆虫OBPs的稳定性和多功能性暗示其可广泛应用于害虫防治、生物传感器、分析化学、生态学等多个领域。本文对过去20多年来昆虫OBPs的相关研究进行综述,为进一步深入开展OBPs的功能研究提供理论参考。  相似文献   
89.
中老年食蟹猴群体自发型糖尿病的筛选   总被引:1,自引:0,他引:1  
Wan YL  Zhang YC  Peng BL  Li XJ  Ji F  Jin LS  Rao JH  Liu XM 《动物学研究》2011,32(3):307-310
筛选440只中老年偏胖食蟹猴群体中自发糖尿病个体,并探讨食蟹猴群体中糖尿病粗筛的方法。以调查基础血糖值为基础,推断疑似糖尿病血糖值,后经OGTT(口服糖耐量)和尿检结果验证该血糖值是否准确。结果显示中老年偏胖食蟹猴群体血糖值为(3.88±0.98)mmol/L,其中56只食蟹猴血糖值大于5.0mmol/L,被初步定为糖尿病个体。这些个体全部糖耐量异常,且36只(69.23%)出现尿糖阳性,证明血糖值大于5.0mmol/L可作为本群体食蟹猴糖尿病的粗筛标准。由于针对中老年偏胖食蟹猴群体,患病率为12.72%(56/440),高于我国糖尿病患病率(9.7%)。虽然该实验的糖尿病血糖指标并不适用于所有食蟹猴群体,但是该筛选的流程简单快捷,对动物损伤小,可适用于大群体糖尿病的筛选。  相似文献   
90.
Vascular endothelial growth factor (VEGF) promotes the growth of solid tumor mainly via VEGF receptor-1 and receptor-2, which are expressed preferentially in proliferating endothelial cells. Therefore, a strategy for simultaneous blockage of both VEGF receptors may have a useful therapeutic effect in tumor growth. In this study, we utilized a fusion protein which is composed of receptor binding domain of VEGF-A (RBDV) and the constant region fragment (Fc) of a human immunoglobulin G1 (IgG1), to interfere with the growth of human umbilical vein endothelial cells (HUVECs) via VEGF receptors. The results showed that RBDV-IgG1 Fc was able to bind with both VEGF receptor-1 and receptor-2. In addition, RBDV-IgG1 Fc could decrease VEGF-induced proliferation and tube formation among HUVECs. Moreover, the cytotoxic test showed RBDV-IgG1 Fc could also enhance the cytotoxic activity of human natural killing cells. The data are suggesting that the fusion protein, RBDV-IgG1 Fc, may have potential as an angiogenesis antagonist for future tumor therapy.  相似文献   
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